> I believe the post-sunrise peak is high-angle for the following
> reason. Beverages and verticals are both low-angle antennas and
> are therefore very complementary.
> So yes, I believe there IS a post-sunrise peak, especially for high-
> angles. W4ZV
What I see is similar.
At times when there is a mag storm, everything works like it does some days
(nowhere near ALL days) at sunrise when there is scattering and severe
multipath. While the AGC of a receiver masks the fading, it is severe and
the ripple is about 10dB or so deep.
This is clearly from interference from multiple arrivals, and nothing cures
it except eliminating all paths but one. I see considerably LESS of the
rapid short-term rapid level change on the most directive antennas. Mixing
antennas is always a disaster, and closer spaced directive antennas .
At night with no severe geo-storms, the low dipole wins within about 100-150
miles...never any more than 200 mi. Beyond that, the omni vert and the
dipole are even broadside to the dipoles, but of course the dipoles are
10-20dB down off their ends. The difference to a low dipole at a distance
is profound, sometimes S5-6 on the LOW dipole when I am steady at well over
9 on the omni vertical.
At or near sunrise on *most* mornings, my low dipole (~130feet) and high
dipoles (~300 feet) and verticals all move very close together. The high
dipole OR a vertical with the same directive gain are a toss up. The low
dipole always looses by some amount beyond a few hundred miles, but at least
is much closer to the other two at any distance. The Beverages work much
worse as do other directive antennas, but sharp vertical arrays retain more
but not all of the original S/N advantage.
This is all based on a few years of steady A-B tests almost every morning
that amounted to over 1000 comparisons, some observations in the evenings
that probably only totaled a few dozen, and continuing occasional tests.
It's easy to see the general trend could be interpreted several ways,
because of local soil conditions and the construction of antennas. If we
read closely, and consider easily accounted differences in antenna
efficiency and patterns, almost everyone who has a variety of antennas with
similar gains agrees.
I don't see anyone with a variety of antennas disagreeing with anything than
can not be accounted for with normal changes in efficiency and pattern.
Where we get into trouble is with "my way or no way" "it will do this by xx
amount" proclamations, when the ionosphere is a complex soup of wildly
changing effects that no one can pin down. We can pin down and define some
things all the time, many things over an average of time, some things
more-often-than-not in time, and some things are just a mess. The ionosphere
teeters between the last two, especially at turbulent times like SR or
storms.
73 Tom
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